Pediatric ALL (Acute Lymphoblastic Leukemia) Patients Had Similar Outcomes Regardless of Participation in Clinical Trials at Seattle Children’s

Findings do not apply to high-risk ALL or other cancers

In a 10-year retrospective study, patients being treated at Seattle Children's Hospital for pediatric acute lymphoblastic leukemia (ALL) had similar outcomes, whether or not they received the standard course of treatment or they participated in a clinical trial. It is often assumed that those who participate in clinical trials for cancers may do better, but in this case there was no difference. The study looked only at newly diagnosed cases of pediatric acute lymphoblastic leukemia; patients with recurring cases or other types of higher risk cancers were not studied. The study also confirmed that patients referred to Seattle Children’s from distant sites did equally as well as their Seattle peers. Led by pediatric oncologist Blythe Thomson, MD, from Seattle Children's Research Institute, the study reinforces that current high standards of evidence-based care provided for children with ALL are leading to good outcomes. The study published in the March issue of Archives of Pediatric & Adolescent Medicine.

“At Seattle Children’s, each of our ALL patients are treated with the same thoroughness and attention to strict, evidence-based protocols, whether or not families are participating in a clinical trial,” said Thomson, clinical associate professor at Seattle Children’s. “Our cure rates are 10% above the national norm. We have the success rates we have today because of the advancements made over the last forty years in previous clinical trials. Families may choose to participate in studies for various reasons, and the practice of medicine has always been improved by those who make research possible. Parents and patients should know that participation in any trial will always remain their choice.”

“Our study shows that currently there are no differences in outcome with clinical trial participation, however, patients do exceptionally well because of the standard practice guidelines that are used every day by clinicians at Seattle Children’s. Any discussions with families about participating in clinical trials for ALL should focus on increasing knowledge about the disease and influencing future therapies, rather than a possible direct benefit for an individual patient research participant,” said Thomson.

Acute lymphoblastic leukemia is a cancer of the white blood cells, which normally help to fight infections. There are two main types of white blood cells, known as lymphoid and myeloid. ALL affects the lymphoid white cells, and it is the most common leukemia and type of cancer in children, representing 23 percent of cancer diagnoses among children younger than 15 years of age. The abnormal white cells are immature and cannot help the body fight infections. For this reason, children with ALL typically suffer from fevers and recurrent infections.

Treatment standards for pediatric ALL have seen dramatic improvements during the last 40 years. In the 1960s, less than five percent of children with ALL survived for more than five years, while today about 85 percent will live five years or more, according to the National Cancer Institute.

This study looked at 322 patients initially diagnosed with ALL prior to age 22, who received their initial therapy at Seattle Children’s between 1997 and 2005. Half of the patients received care that was standard at the time, and half were participants in a clinical trial. During this same period, treatment protocols were rigidly standardized at Seattle Children’s, based upon the most current research. These new standards may have provided the same benefit as participating in studies, according to the researchers.

“Similar outcomes results may not be found at other hospitals, or for other types of cancers,” said Thomson. “Our data reflects the care standards we have in place in our regional cancer referral center, from a specific time period, and for this specific illness.”


  • If your child is diagnosed with ALL or any cancer, seek care in a specialty pediatric cancer center that treats larger numbers of pediatric cancer patients and has data showing good survival rates.
  • Ask your child’s oncologist (cancer specialist) if they have any open clinical trials you might consider joining.
  • It is always your choice whether or not to take part in any research study.
  • Even if you’ve chosen to take part in a study, you can always change your mind and opt out later.
  • If you’re considering joining a study, ask what the study’s goals are. Make sure you understand what the researchers are hoping to learn.
  • Families considering joining a study should ask where and how their medical information may be used and shared.
  • Ask about what your involvement in the study means for your family. Each study is different.
  • Taking part in a study may (or may not) help lead to care improvements for others in the future.
  • Remember that taking part in a study provides no guarantees for better care or outcomes.
  • All clinical studies are approved and monitored by an Institutional Review Board (IRB) that ensures ethical and safe study protocols (action plans). The IRB protects the rights and interests of patients who are study participants.

For more information about ALL, please visit: or

For more information about participating in clinical trials, please visit:,, or

Thomson’s study collaborators included Carl Koschmann, MD, pediatric resident at Seattle Children’s and the University of Washington School of Medicine, who performed the majority of data collection and is lead author on the manuscript, and Douglas S. Hawkins, MD, associate division chief of hematology/oncology at Seattle Children’s and associate professor of pediatrics at the University of Washington School of Medicine.

About Seattle Children’s Research Institute

Located in downtown Seattle’s biotech corridor, Seattle Children’s Research Institute is pushing the boundaries of medical research to find cures for pediatric diseases and improve outcomes for children all over the world. Internationally recognized investigators and staff at the research institute are advancing new discoveries in cancer, genetics, immunology, pathology, infectious disease, injury prevention and bioethics, among others. As part of Seattle Children’s Hospital, the research institute brings together leading minds in pediatric research to provide patients with the best care possible. Seattle Children’s serves as the primary teaching, clinical and research site for the Department of Pediatrics at the University of Washington School of Medicine, which consistently ranks as one of the best pediatric departments in the country. For more information, visit